I haven't really kept up with the PSLs but I think the M models are just 100% commercial models, they're not made with any parts from parts kits or old stocks of communist parts from the warehouses. They're new manufactured parts only and built for the commercial market here in the US and in other countries that don't allow them to be imported in with military features like the bayonet lug, flash hider, or restrict the resell of former military weapons.